Sister often says that sister-in-law is a fool. Although she is joking, she also makes her children angry. How should I educate my sister?

The quality of the sister of the landlord is not very high. It may be said that the landlord will be unhappy, but the fact is that she doesn't know how to respect her elders. People like her are not worthy of respect, and often such people can't change their habits. Therefore, if your sister is old, then many years will be in vain, and education will be useless, because it has already taken shape. People like her are even worse than dogs. It is an insult to say that she is a dog. If she is young, she should be educated quickly so that she can learn to respect and care for others. If others say she is a fool, will she be content? After education, she may get better.